Pressurized liner

ABSTRACT

A pressurized liner ( 10 ) is disclosed for use with a bulk container. The pressurized liner has a central band ( 12 ), two inner caps ( 13 ), and two outer caps ( 14 ). Each inner cap has an end wall ( 20 ) and four peripheral side walls ( 21 ). Each outer cap has an end wall ( 22 ) and four peripheral side walls ( 23 ). The central band and inner caps define a central compartment ( 33 ) which has an inlet port ( 34 ) and an outlet port ( 36 ). Each adjoining pair of inner caps and outer caps define inflatable side compartments ( 39 ) coupled to opposite sides of the central compartment. Each inflatable side compartment has a pressurized air port ( 40 ) to allow inflation and deflation of the side compartment. The inner caps have a lateral depth (d 1 ) generally equal to or greater than a lateral depth (d 2 ) of the outer caps.

TECHNICAL FIELD

This invention relates to bulk material liners used in conjunction with bulk containers, and particularly to intermediate bulk container liners which are pressurized to enhance the evacuation of contents.

BACKGROUND OF THE INVENTION

Flexible liners are oftentimes utilized in conjunction with an intermediate bulk container or bag to ship large quantities of liquid, viscous or granular products. A problem long associated with the use of such liners has been the complete or near-complete evacuation of the contents from within the liner. As such, some liners have utilized pressurized regions to lift or angle the bottom of the liner in order to move the contents closer to the outlet of the liner. While these devices have aided in the evacuation of the liner they can still result in rather large quantities of content remaining within the liner.

Accordingly, it is seen that a need remains for an intermediate bulk container liner that can more efficiently evacuate the contents. It is to the provision of such therefore that the present invention is primarily directed.

SUMMARY OF THE INVENTION

A pressurized liner for use with a intermediate bulk container comprises a tubular central band having at least one content port and at least one open end defined by a peripheral edge, at least one inner cap sealed to the tubular central band open end and at least one outer cap sealed to the tubular central band open end. The inner cap has an inner cap end wall and peripheral inner cap side walls extending from the inner cap end wall. The outer cap has an outer cap end wall and peripheral outer cap side walls extending from the outer cap end wall. The outer cap has an air inlet port extending therethrough. The inner cap and outer cap define an expandable pressure compartment therebetween in fluid communication with the outer cap air inlet port. With this construction, the inflation of the expandable pressure compartment moves the inner cap to a position within the central band.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a pressurized liner embodying principles of the invention in a preferred form.

FIG. 2 is an exploded, perspective view of the pressurized liner of FIG. 1.

FIGS. 3-8 are a series of side views of the pressurized liner of FIG. 1, showing the liner being pressurized.

DETAILED DESCRIPTION

With reference next to the drawings, there is shown a pressurized liner 10 embodying principles of the invention in a preferred form. The pressurized liner 10 is configured to be used in conjunction with an intermediate bulk container, which can be in the form of a flexible bag, a rigid container or a semi-rigid container.

The pressurized liner 10 includes a tubular central band or portion 12, two oppositely disposed inner caps 13, and two oppositely disposed outer caps 14. The central band 12 has two oppositely disposed peripheral edges 16 which are laterally spaced from each other and which are sealed to an inner cap peripheral edge 17 and an outer cap peripheral edge 18 so as to define two vertically oriented, circumferential, peripheral seals 19. All peripheral edges 16, 17 and 18 may also be termed peripheral rims.

Each inner cap 13 has an end wall 20 and four peripheral side walls 21 extending generally normal to and laterally from the end wall 20 so as to define a generally open box shape configuration, the opening of such facing the central band 12. The open box shape can be described generally as a rectangular prism, although it should be understood that due to the bellowing of flexible plastic materials the walls of the rectangular prism are not perfectly straight and some bowing or bellowing occurs. The side wall 21 which forms a bottom side wall 21′ may be considered to be a bottom. Similarly, each outer cap 14 has an end wall 22 and four peripheral side walls 23 extending generally normal to and laterally from the end wall 22 so as to define a generally open box shaped configuration, the opening of such facing the central band 12. Again, the side wall 23 which forms a bottom side wall 23′ may be considered to be a bottom. The central band 12 and the inner caps 13 are preferably of a two or three ply construction while the outer caps 14 are of a single ply construction. The central band 12 and caps 13 and 14 may be made of a plastic sheet or film material such as a polyethylene film.

The central band 12 and inner caps 13 define a middle or central compartment 33 which has a content inlet port or fitment 34 sealed to and extending through the top wall 35 of the central band and a content outlet port or fitment 36 sealed to and extending through a front wall 37 of the central band. Each adjoining or adjacent pair of inner caps 13 and outer caps 14 define inflatable side compartments 39 coupled to opposite sides of the central compartment 33. Each inflatable side compartment 39 has a pressurized air port or fitment 40 to allow the passage of pressurized air therethrough to inflate and deflate the side compartment 39.

The inner caps 13 have a substantially similar three dimensional lateral depth d1 extending between their respective peripheral edges 17 and their end walls 20. Similarly, the outer caps 14 have a substantially similar or slightly smaller three dimensional lateral depth d2 to that of d1 between their respective peripheral edges 18 and their end walls 22 to insure that the inner caps contact the outer caps when in an extended configuration. As such, each inner cap 13 depth d1 is selected so as to nest flush within and generally against the adjacent outer cap 14 when the central compartment 33 is filled with contents (filled configuration), as shown in FIGS. 1 and 3. The inner cap 13 selected depth d1 is also selected so that the inner caps 13 generally contact each other when the side compartments 39 are inflated and the central compartment is substantially emptied or evacuated of content (emptied configuration), as shown in FIG. 8. In other words, the inner cap selected depth d1 substantially equals or is greater the outer cap selected depth d2 so that they are flush with each other.

In use, with the inner caps extending outwardly against the outer caps, the contents to be stored within the liner, such as a liquid, powder, granules, etc., flow into the central compartment 33 through the content inlet port 34. As the content fills the central compartment 33 the inner caps 13 are forced to move outwardly or are maintained outwardly against the outer caps 14, as shown in FIGS. 1 and 3, until the central compartment 33 is full. The inlet port 34 is then sealed or closed and the liner and container combination may be transported.

When it is desired to empty or evacuate the contents from the liner 10 the content outlet port 36 is opened so that the contents may flow through the outlet port 36 to ambience. An air pressure source is also coupled to the air ports 40 of the side compartments 39 so that pressurized air flows into and thereby inflates the side compartments 39 during the evacuation process. Initially, the pressurized air inflates only the topmost portion of the side compartments, as shown in FIG. 4. With continued evacuation of the contents and additional airflow into the side compartments 39, the side compartments become inflated to a greater degree and thereby extend inwardly towards and into contact with each other, as shown sequentially in FIGS. 5 and 6. As the contents within the central compartment 33 are evacuated to a very low level and with continued air pressurization of the side compartments, the end walls 31 of the inner caps are pulled completely away from the end walls 32 of the outer caps and they commence to roll upon the underlying bottom side wall or bottom 21′ of the inner cap, as shown in FIG. 7. Finally, the air pressure within the side compartments force the inner caps inwardly so that are fully extended thereby pushing and squeezing a substantial portion of any remaining contents from the central compartment through the content outlet port 36. As such, it should be understood that the inner caps commence in a fully outwardly extended position (filled configuration) extending outwardly from the central band 12 and against the outer caps and are then inverted to a fully inwardly extended position (emptied configuration) fully within the central band 12 and against each other. The rolling of the inner cap against its own bottom side wall 21′ aids in pushing the vast majority of any remaining content material towards and through the outlet port 36.

It should be understood that the three dimensional configuration of the inner cap, as opposed to the prior art pressure chambers formed by merely sealing the peripheral edges of flat sheets together (a pillow type liner), provides for a great amount of pushing ability or characteristics upon the contents, especially in the lower portion of the central compartment 33 adjacent the bottom of the central compartment with the rolled action of the inner cap adjacent the bottom side wall 21′. This enhancement provides for a greater degree of content movement or evacuation through the content outlet port 36.

It should be understood that should the pressurized liner include only one set of inner and outer caps the opposite end of the tubular central band is closed in conventional fashion with an end wall, i.e., the pressurized liner has only one side compartment. Lastly, it should be understood that as an option the liner may include only one port which acts as both the content inlet port and the content outlet port.

It thus is seen that a pressurized liner is now provided which overcomes problems associated with pressurized liners of the prior art. While this invention has been described in detail with particular references to the preferred embodiments thereof, it should be understood that many modifications, additions and deletions, in addition to those expressly recited, may be made thereto without departure from the spirit and scope of the invention. 

1. A pressurized liner for use with an intermediate bulk material container, said pressurized liner comprising, a tubular central band having at least one content port and at least one open end defined by a peripheral edge; at least one inner cap sealed to said tubular central band open end, said inner cap having an inner cap end wall and peripheral inner cap side walls extending from said inner cap end wall, and at least one outer cap sealed to said tubular central band open end, said outer cap having an outer cap end wall and peripheral outer cap side walls extending from said outer cap end wall, said outer cap having an air inlet port extending therethrough; said inner cap and said outer cap defining an expandable pressure compartment therebetween in fluid communication with said outer cap air inlet port, whereby the inflation of the expandable pressure compartment moves the inner cap to a position within the central band.
 2. The pressurized liner of claim 1 wherein said inner cap has a select first depth extending from said inner cap end wall and wherein said outer cap has a second select depth extending from said outer cap end wall, and wherein said first depth is generally the same as or greater than said second depth.
 3. The pressurized liner of claim 1 wherein said central band has a second open end defined by a second peripheral edge, and wherein said liner further comprises a second inner cap sealed to said tubular central band second open end, said second inner cap having a second inner cap end wall and peripheral second inner cap side walls extending from said second inner cap end wall, and a second outer cap sealed to said tubular central band second open end, said second outer cap having a second outer cap end wall and peripheral second outer cap side walls extending from said second outer cap end wall.
 4. The pressurized liner of claim 3 wherein said second outer cap has a second air inlet port extending therethrough.
 5. The pressurized liner of claim 3 wherein said second inner cap has a select third depth extending from said second inner cap end wall and wherein said second outer cap has a fourth select depth extending from said second outer cap end wall, and wherein said third depth is generally the same as or greater than said fourth depth.
 6. The pressurized liner of claim 1 wherein said inner cap and said outer cap are sealed to said central band along a common seal.
 7. A pressurized liner for use in conjunction with an intermediate bulk container comprising, a central compartment having at least one content port, and a side compartment coupled to said central compartment, said side compartment having an open box shaped inner cap and an open box shaped outer cap coupled to said open box shaped inner cap about a peripheral rim of said box shaped outer cap, said open box shaped inner cap being moveable between a first position generally flush against an interior surface of said box shaped outer cap and a second position positioned within said central compartment, said open box shaped outer cap having an air inlet therethrough.
 8. The pressurized liner of claim 7 wherein said box shaped inner cap and said box shaped outer cap are shaped generally as rectangular prisms.
 9. The pressurized liner of claim 7 wherein said box shaped inner cap has a select first depth and wherein said box shaped outer cap has a second select depth, and wherein said first depth is generally the same as or greater than said second depth.
 10. The pressurized liner of claim 7 further comprising a second side compartment coupled to said central compartment, said second side compartment having a second open box shaped inner cap and a second open box shaped outer cap coupled to said second open box shaped inner cap about a second peripheral rim of said second box shaped outer cap, said second open box shaped inner cap being moveable between a first position generally flush against an interior surface of said second box shaped outer cap and a second position positioned within said central compartment.
 11. The pressurized liner of claim 10 wherein said second open box shaped outer cap has a second air inlet port extending therethrough.
 12. The pressurized liner of claim 10 wherein said second open box shaped inner cap has a select third depth and wherein said second open box shaped outer cap has a fourth select depth, and wherein said third depth is generally the same as or greater than said fourth depth.
 13. The pressurized liner of claim 7 wherein said open box shaped inner cap and said open box shaped outer cap are coupled to said central compartment along a common seal.
 14. The pressurized liner of claim 10 wherein said second open box shaped inner cap and said second open box shaped outer cap are coupled to said central compartment along a common seal.
 15. A pressurized liner for use with an intermediate bulk container comprising, a central portion having a top wall, a bottom wall, a front wall, and a rear wall which in combination define two oppositely disposed open sides along two oppositely disposed peripheral edges which are laterally spaced from each other, said central portion having at least one content port; a first inner end wall coupled to said central portion about one said peripheral edge; a first outer end wall coupled to said central portion about said one peripheral edge; a second inner end wall coupled to said central portion about the other said peripheral edge; a second outer end wall coupled to said central portion about the other said peripheral edge, and said first inner end wall and said first outer end wall defining a first side compartment therebetween having a first air inlet; said second inner end wall and said second outer end wall defining a second side compartment therebetween having a second air inlet, whereby the flow of air through the first and second air inlets inflate the first and second side compartments so as to squeeze the contents within the central portion through the content port.
 16. The pressurized liner of claim 15 wherein said first inner end wall, said first outer end wall, said second inner end wall, and said second outer end wall are all box shaped caps.
 17. The pressurized liner of claim 16 wherein said first inner end wall, said first outer end wall, said second inner end wall, and said second outer end wall are all box shaped caps of a generally rectangular prism shape.
 18. The pressurized liner of claim 16 wherein said box shaped first inner cap has a select first depth and wherein said box shaped first outer cap has a second select depth, and wherein said first depth is generally the same as or greater than said second depth.
 19. The pressurized liner of claim 18 wherein said box shaped second inner cap has a select third depth and wherein said box shaped second outer cap has a fourth select depth, and wherein said third depth is generally the same as or greater than said fourth depth.
 20. The pressurized liner of claim 15 wherein said first inner end wall and said first outer end wall are coupled to said central portion along a common seal.
 21. The pressurized liner of claim 20 wherein said second inner end wall and said second outer end wall are coupled to said central portion along a common seal. 